B7800 - Busted Axle at 441 hours

[Charlesaf3]

another vote for keeping weight on your 3pt (I use the box blade) AND loaded tires. To my mind they do different things.

And once again, **** happens. Though no doubt its really annoying when it happens to you - I don't blame you for being annoyed. I just had the joystick on my FEL break 2 weeks out of warranty. Annoying. Clearly a manufacturing defect, but one that happens.

 

[twodogs]

another vote for keeping weight on your 3pt (I use the box blade) AND loaded tires. To my mind they do different things.

And once again, **** happens. Though no doubt its really annoying when it happens to you - I don't blame you for being annoyed. I just had the joystick on my FEL break 2 weeks out of warranty. Annoying. Clearly a manufacturing defect, but one that happens.

Thanks Charles. Sorry to hear about your break.

I double checked my manuals & the weight given as needed for a ballast matches the weight of my filled tires. In fact, the manual gives the filled tires as an option. If you have read through the thread you've noticed that the dealer also recommended it as my ballast. Many people on this forum have given good reasons to use an additional ballast and I will use one in the future as "added insurance". I think I am going to get a carry all & build a box for it. There is a great thread on that as well.

 

[milkman]

The way I see it is, ballast is for traction and stability. Weight on the TPH provides traction, but more importantly with a FEL it provides a counterweight to take part of the load off the front axle and transfer it to the rear axle. When using a FEL even with ballasts in the tires or in the form of wheelweights it puts the load of the FEL on the front axle and also transfers part of the weight of the ballast to the front axle when the weight in the bucket tries to lift the rear off the ground. Hope that's clear as mud.

 

[kevinj]

Thanks Charles. Sorry to hear about your break.

I double checked my manuals & the weight given as needed for a ballast matches the weight of my filled tires. In fact, the manual gives the filled tires as an option. If you have read through the thread you've noticed that the dealer also recommended it as my ballast. Many people on this forum have given good reasons to use an additional ballast and I will use one in the future as "added insurance". I think I am going to get a carry all & build a box for it. There is a great thread on that as well.

The 7800 must have different ballast requirement. The B7500 says rear ballast to be added in the form of 3 point counter weight AND rear wheel ballast. It goes on to say that the ballast requirements depend on the application.

If the loader can lift 600# then you need a bit over 600# on the rear to offset the loader weight and the lifted load.

 

[RobJ]

It goes on to say that the ballast requirements depend on the application.

If the loader can lift 600# then you need a bit over 600# on the rear to offset the loader weight and the lifted load.

If you lift 600# you should not need 600# on the rear. The design of the loader should help keep the center of gravity fairly equal, unless you overload as many of us have done.

As you mentioned it depends on the application. IE a loader can lift 600#, doesn't say it's ok to drive at WOT down a washboard road with the weight all the way up!

 

[kevinj]

If you lift 600# you should not need 600# on the rear. The design of the loader should help keep the center of gravity fairly equal, unless you overload as many of us have done.

As you mentioned it depends on the application. IE a loader can lift 600#, doesn't say it's ok to drive at WOT down a washboard road with the weight all the way up!

I figure that if I cannot do moderate loader work in 2 wheel drive or curl the bucket without lifting the tires then I need more rear weight. Many people just put it in 4wd when they spin out and are really to light in the rear. Then backing up with the front pulling tends to lift the rear wheels.

My L3940 gets light in the rear with 2200# of ballast on it which is right about max lift at the pins.

The B7500 has about 800# of ballast and curling back or lifting a full bucket will make the rear light and sometimes even lift a tire. That loader is good for about 600# max.

Kubota does not give specific ballast requirements in the manuals, they leave it up to the operator. My 3940 shows from 450# thru 1700# as implement ballast and says ballast may vary by application. 450# on that tractor is about useless unless you are moving sawdust or mulch.

Gravel, red clay, etc needs all the ballast you get as you are picking the max load for the tractor and loader if the bucket is full. Same holds for using pallet forks when the load is extended out fron even further.

I am old enough to remember and have operated many 2wd loaders including some old payloaders in the gravel pits. These old 2wd units had loaded tires and BIG counterweights.

 

[riptides]

I don't have the maintenance manuals handy, but does any service points actually look to this issue? Something like an inspection point?

Little odd that heavy loader work and improper ballasting will not require a visual on front-end stress points...don't you agree? One would think that if these conditions are to be exceeded, then the operating model would call for some additional inspections.

I'd say it was pure bad luck, and I'd be miffed, and since is not an abuse thing, or outside the operating model, I'd expect Kubota to make it right.

I don't think your expecting too much, but in today's reality, making things right, isn't good business.

 

[rbcsaver]

I had a leaking front axle seal on my 7510 when it was STILL under warranty. Dealer told me it wasn't covered under the warranty and it cost me more than $200.
Steve

 

[crazyal]

First off let me say that I probably would be upset too. But I don't think axles are cast, most likely they are forged. Looking at your picks you can clearly see the rust line that shows it was half broke for some time.

As a NDT specialest I would disagree with those who say it came from the factory that way. A defect like that would have been picked up by QA. Usually (never been to the axle shop at Kubota) the forgings are checked before machining to reduce the cost of machining a bad part. After it's machined it's not unusual to check it a second time.

I don't think just overloading your FEL would have broken it in that way. Maybe if you had it loaded and hit something hard with your front wheel or a hole of some sort (not that I'm saying you did) or maybe when it was new at the dealership it was dropped in some way. It's very possible that your gentle use prolonged it's life.

It's a pretty long post but did you say the other axle shows signs of also cracking?

Again it sounds to me like you did nothing wrong. But ask yourself this question, what if it was something you did, how would Kubota know? So they are also taking your word.

 

[Ken]

400 hour before 1st. real problem.and now want parts and labor free.
My L3600 only part not repaired was the transmission. front end diff. twice front wheel gears. rear axle gear cracked ,engine rebuild ,steering system kept blowing seals and when adding total repair parts times the hours run came to about $50.00 per hour use. at 1500 hours could not sell at price wanted. gave it to a retired man to use only for mowing yard. He now avoids me and when asked about the tractor says not used lately.
The amount the dealier wants to repair 75/80 per hour less than a days work.
Just my thinking.
ken